Computer Graphics - Department of Aerospace …ae.sharif.edu/~aerocad/Computer...
Transcript of Computer Graphics - Department of Aerospace …ae.sharif.edu/~aerocad/Computer...
Computer Graphics
Introduction to Computer Graphics, Anirban Mukhopadhyay, ArupChattopadhyay
COMPUTER GRAPHICS, Donald Haern, M. Pauline Baker (Second Edition)
روشهاي مدلسازي در محيط مجازي كامپيوتر، دكتر سيدمحمدباقر مالئك، معصومه يونسي
Textbook:Sunday/Tuesday 13:30-15Time:
Modeling
Computers have become a powerful tool for the rapid and economical production of pictures and models.
There is no area in which graphics displays cannot be used to some advantage.
What is Computer Graphics?
Computer graphics generally means creation, storage and manipulationof models and images.
What is Computer Graphics?
Such models come from diverse and expanding set of fields including physical, mathematical, artistic, biological, economical, … .
Model
Model, models, or modeling: a pattern, plan, representation, or description designed to show the structure or working of an object, system, or concept.
Physical Model
A physical model is used to mean a physical representation of some things, for example a bolt or the solar system.
Physical Model
A scale model of the Singapore City Centre.
The geometry of the model and the object it represents are often similar in the sense that one is a rescaling of the other.
Mathematical ModelA mathematical mode: it uses mathematical language to describe the behaviour of a system.
Mathematical models are used in the science, engineering, economics and …
Mathematical Model
A mathematical model describes a system by a set of variables and a set of equations that establish relationship between the variables.
Economic Model
In economics, a model is a theoretical construct that represents economic processes by a set of variables and a set of logical and quantitative relationships between them.
What is Computer Graphics?William Fetter coined term “computer graphics” in 1960 to describe new design methods he was pursuing at Boeing.
Created a series of widely reproduced images on pen plotter exploring cockpitdesign, using 3D model of human body.
What is Computer Graphics?“Perhaps the best way to define computer graphics is to find out what it is not. It is not a machine. It is not a computer, nor a group of computer programs. It is not the know-how of a graphic designer, a programmer, a writer, a motion picture specialist, or a reproduction specialist.
Computer graphics is all these – a consciously managed and documented technology directed toward communicating information accurately and descriptively.”
What is Interactive Computer Graphics?
User controls contents, structure, and appearance of objects and their displayed images via rapid visual feedback.
Interactive Computer GraphicsBasic components of an interactive graphics system:
input (e.g., mouse, tablet and stylus, scanner…)processing (and storage)display/output (e.g., screen, paper-based printer, video recorder …)
First truly interactive graphics system, Sketchpad, pioneered at MIT by Ivan Sutherland for his 1963 Ph.D. thesis.
Sketchpad in 1963. Note use of a CRT monitor, light pen and function-key panel.
Interactive Computer Graphics
Before Sketchpad, output via plotters/printers, input via keypunch.
Card punching. IBM 704 . took up a whole room and was capable of about 4,000 arithmetic operations/second.
Interactive Computer Graphics
“The Sketchpad system uses drawing as a novel communication medium for a computer. The system contains input, output, and computation programs which enable it to interpret information drawn directly on a computer display. ”
Interactive Computer Graphics
“Sketchpad has shown the most usefulness as an aid to the understanding of processes, such as the motion of linkages, which can be described with pictures. Sketchpad also makes it easy to draw highly repetitive or highly accurate drawings and to change drawings previously drawn with it…”
Interactive Computer Graphics
Interactive Computer GraphicsCost/Time ($/hr): Whirlwind, built in early 50’s at MIT, cost $4.5 million and could perform 40,000 additions/second. Mac 512K, list price $3,195 in 1984, could do 500,000. Today, commodity PCs perform approximately two or three billion operations/second.
Quality: Eliminates error propagation by using data bases and transfer of data.
Interactive Computer Graphics
Applications
Computer Aided DesignPresentation GraphicsComputer ArtEntertainmentEducation and trainingVisualizationImage ProcessingGraphics User Interfaces
ApplicationsComputer Aided Design (CAD)
A major use of computer graphics in design processes, particularly for engineering and architectural system. But almost all product are now computer designed.
ApplicationsComputer Aided Design (CAD)
For some design applications, objects are first displayed in a wireframeoutline form.
Wireframe (outline) form shows the overall shape and internal features of objects.
ApplicationsComputer Aided Design (CAD)
Software package for CAD applications typically provide the designer with a multi-window environment.
ApplicationsComputer Aided Design (CAD)
Circuits designed by successively placing components into the layout, with the graphics package automatically providing the connections between components.
ApplicationsComputer Aided Design (CAD)
Animation are often used in CAD applications.
Animation in virtual reality environment are used to determine how system operators are affected by certain motion.
ApplicationsComputer Aided Design (CAD)
The manufacturing process is also tied in to the computer description of designed objects to automate the construction of the product.
ApplicationsPresentation Graphics
Presentation graphics used to product illustrations for reports or to generate 35-mm slides or transparencies for use with projectors.
ApplicationsPresentation Graphics
Presentation graphics is used to:StatisticalMathematicalScientificEconomic dataManagerial reportConsumer information bulletins
ApplicationsPresentation Graphics
Typical examples of presentation graphics are:
Bar GraphsLine GraphsSurface GraphsPie Charts
ApplicationsPresentation Graphics
Typical examples of presentation graphics are:
HistogramTask Schedule ChartInventory ChartProduction Chart
ApplicationsPresentation Graphics
Histogram: A histogram is the graphical version of a able which shows what property of cases fall into each of several or many specified categories.
ApplicationsPresentation Graphics
Task Scheduling chart: In project management, a schedule consists of a list of a project’s terminal elements with intended start and finish dates.
ApplicationsComputer Art
Computer graphics are widely used in both fine art and commercial artapplications.
ApplicationsComputer Art
Fine ArtPaintbrush Program:It allows artists to “paint” pictures on the screen of a video monitor.
ApplicationsComputer Art
Commercial ArtLogosPage layout (Combining text and graphics)
TV Advertising Spots
ApplicationsComputer Art
Commercial ArtMorphing: Where one object is transformed (metamorphosed) into another.
ApplicationsEntertainment
Computer graphics are now commonly used in making motion pictures, music video, and television shows.
ApplicationsEducation and Training
Models of physical systems, physiological systems, population trends can help trainees to understand the operation of the system.
ApplicationsEducation and Training
For some training applications, special systems are designed.
Color-coded diagram used to explain the operation of a nuclear reactor.
ApplicationsEducation and Training
Special systems are the simulators for practice session or training of ship captains, aircraft pilots, and air traffic control personnel.
ApplicationsVisualization
Producing graphical representation for scientific, engineering, and medical data sets and processes is generally referred to as scientific visualization.The term business visualization is used in connection with data sets related to commerce, industry, and other nonscientific areas.
ApplicationsImage Processing
Image processing applies techniques to modify or interpret existing pictures, such as photographs and TV scans.
Medicine uses these techniques to model and study physic functions, to artificial limbs, and to plan and practice surgery.
ApplicationsGraphics User Interfaces
A major component of a graphical interface is a window manager that allows a user to display multi-window areas.